Gray leaf spot of corn is caused by a fungal pathogen Cercospora zeae-maydis (Syn. • They increase in size and become dark brown. Abstract: Grey leaf spot is a serious yield-reducing disease of maize (Zea mays) in many parts of the world where this crop is cultivated. Phaeosphaeria leaf spot (PLS) is increasingly being considered a major disease of maize in parts of South Africa, especially in KwaZulu-Natal in the mist belt, Winterton and Bergville areas and is considered a potential threat to maize production in regions … Causal Organism. The causal organism associated with the disease is Cercospora zeae-maydis. Mycosphaerella spp). 1. Models were developed to assess the risk and predict the severity of gray leaf spot of maize, and to describe relationships between environmental variables and the rate of lesion expansion and sporulation of the causal organism, Cercospora zeae-maydis. Maize bushy stunt Mycoplasmalike organism (MLO), assoc. 2006; 55:189–197. Symptoms and Management of FrogEye Leaf spot Tobacco: Causal organism: Cercospora nicotianae. Cercospora zeina is the causal agent of grey leaf spot disease of maize in southern Africa. History and distribution of gray leaf spot of maize The first report of gray leaf spot (GLS) of maize, caused by Ce/cospora zeae-mayd/s Tehon and Daniels, dates back to 1924 when the disease was observed in Alexander County, southern Illinois (58). The aim of our study was to identify the causal agent of grey leaf spot disease of maize in southern Africa. The disease is caused by Cochliobolus lunatus (syn. Causal Organism. Ring Criconemella spp. Dagger, American Xiphinema americanum: Lesion Pratylenchus spp. Grey leaf spot disease (GLS), Cercospora zeae-maydis, which has previously been attributed to diverse pathogen species in other countries, has become a serious biotic constraint to production of maize (Zea mays L.) in Kenya. Grey leaf spot is a serious yield-reducing disease of maize (Zea mays) in many parts of the world where this crop is cultivated. E-mail: foyedeji@yahoo.com. Starts on lower leaves progressing upwards Management and Control 1. Two potential sibling species have been recognized as Groups I and II. Two potential sibling species have been recognized as Groups I and II. Eur J Plant Pathol. Grey leaf spot (GLS), caused by Cercospora zeae-maydis or Cercospora zeina, is a highly destructive foliar disease worldwide. The causal organism associated with the disease is Cercospora zeae-maydis. Gray leaf spot lesions on corn leaves hinder photosynthetic activity, reducing carbohydrates allocated towards grain fill. A major QTL repeatedly detected in multiple developmental stages and environments was fine mapped in a backcross population. Reniform Rotylenchus spp. Nematodes, parasitic. Spiral Helicotylenchus spp. 892. The causal organism a… It has become well established in the province of KwaZulu-Natal, and is capable of reducing grain yields by 20 to 60%. Grey leaf spot is a serious yield-reducing disease of maize (Zea mays) in many parts of the world where this crop is cultivated.The causal organism associated with the disease is Cercospora zeae-maydis.Two potential sibling species have been recognized as Groups I and II. Grey leaf spot is a relatively new fungal disease of maize in South Africa. Single-conidial cultures were recovered from maize leaves with typical disease symptoms sampled from several fields in South Africa, Zambia Maize Leaf Spot Causal Organism masuzi January 20, 2020 Uncategorized 0 Northern corn leaf spot umn extension gray leaf spot of corn ohioline northern corn leaf blight pioneer seeds leaf blight of maize … This study was conducted to establish solutions to the problem that could be easily implemented by maize farmers. Northern leaf spot (=Helminthosporium leaf spot) Causal organism: Cochliobolus carbonum Nelson, Ascomycotina . Lesions are about 0.5 cm in diameter when fully developed. The disease begins to occur around the rainy season and stripe lesions are produced along the midrib abundantly. Two potential sibling species have been recognized as Groups I and II. Phaeosphaeria leaf spot CAUSAL ORGANISM Fungus: Phaeosphaeria maydis and Phoma sorghina (possible disease complex). Although both diseases are restricted by leaf veins, the margins of BLS lesions are irregular, whilst those of GLS have a rectangular appearance (Photo 3). In recent years, gray leaf spot (GLS) has become a major yield‐limiting disease, resulting in grain yield losses as high as 60% in high yield potential maize (Zea mays L.) production areas. Root-knot Meloidogyne spp. Maize chlorotic dwarf Maize chlorotic dwarf virus (MCDV) Maize chlorotic mottle Maize chlorotic mottle virus (MCMV) Maize dwarf mosaic Maize dwarf mosaic virus (MDMV) strains A, D, E and F Maize leaf fleck Maize leaf fleck virus (MLFV) Maize line* Maize line virus (MLV) on Curvularia lunata, the causal organism of maize leaf spot O. CAUSAL ORGANISM: Exserohilum turcicum (previously called Helminthosporium turcicum) Grey-green, elliptical disease lesions begin to develop 1 to 2 weeks after infection (Figure 1). The lesions may merge forming large grey blotches with irregular margins killing the leaves 3. The causal organism associated with the disease is Cercospora zeae-maydis. Small yellowish round to oval spots are seen on the leaves. Grey leaf spot is a serious yield-reducing disease of maize (Zea mays) in many parts of the world where this crop is cultivated. Maize leaf showing symptoms of Curvularia leaf spot: small necrotic or chlorotic spots with a light colored halo. ... BLS disease symptoms can easily be confused with that of a fungal disease named grey leaf spot (GLS). The pustules are generally small, less than 0.6 cm, and are surrounded by the leaf epidermal layer which appears as a whitish covering. Contents1 Stem rot of rice management1.1 Causal organism of Stem … Stem rot of rice management Contents1 FrogEye Leaf spot 1.1 Symptoms of FrogEye Leaf spot Tobacco1.2 … Needle Longidorus africanus and other species Pin Paratylenchus spp. The fungus affects the maize plant at a young stage. Lesions are pale brown or grey to tan, long, narrow and rectangular, being characteristically restricted by veins 2. The sexual stage producing ascospores was found in the fungus infecting rice, and so the rice blast fungus is generally called Magnaporthe grisea.In turfgrasses, ascospores have not been observed, and the gray leaf spot fungus is referred to as Pyricularia grisea.Host range of the fungus is more than 50 grass species, including wheat, crabgrass, and foxtail. The aim of our study was to identify the causal agent of grey leaf spot disease of maize in southern Africa. The causal organism associated with the disease is Cercospora zeae-maydis. Small roundish spot are developed on the leaves, especially on The genetic basis of GLS resistance was dissected using two DH populations sharing a common resistant parent. 1) Turcicum Leaf blight: causal organism: Helminthosporium turcicum. Disease name: Mango Grey Blight Causal Organism: Pestalotiopsis mangiferae Pestalotia mangiferae (Syn) Other names: Pestalotiopsis Leaf Spot of mango Report: First reported by Hennings in Taiwan at 1909. doi: 10.1007/s10658-009-9443-1. Spot-causing fungal disease occurring increasingly mainly in the cool region. Accepted June 22, 2010 The efficacy of leaf extracts of Gliricidia sepium, Tithonia diversifolia, Phyllanthus amarus and Morinda lucida were assessed in vitro to control Curvularia lunata. Curvularia maculans). Species of Cercospora associated with grey leaf spot of maize. The disease is spreading to neighbouring provinces and countries. Causal organism: Fungus: Cercospora zea-maydis Symptoms: 1. Stud Mycol. BLS of maize The causal organism of BLS is Xanthomonas vasicola pv. Nematodes, parasitic; Awl Dolichodorus spp. Symptoms • Brown spots develop on the margin and at the tip of the leaf lamina. 2009; 124:577–583. Abstract: Grey leaf spot is a serious yield-reducing disease of maize (Zea mays) in many parts of the world where this crop is cultivated. I MPORTANC. Curvularia lunata ), Pseudocochliobolus pallescens (syn. The spots develop into oval to elongate reddish-brown powdery and elevated lesions that contain a powdery mass of orange to reddish-brown spores on the upper and lower leaf surfaces. Sting Belonolaimus … Grey leaf spot is a serious yield-reducing disease of maize (Zea mays) in many parts of the world where this crop is cultivated. Crous PW, Groenewald JZ, Groenewald M, Caldwell P, Braun U, Harrington TC. Zonate leaf spot and sheath blight Gloeocercospora sorghi. Grey Leaf Spot. A. Akinbode Institute of Agricultural Research and Training, IAR&T, Ibadan, Nigeria. Grow Seed Co tolerant hybrids 2. The spores became brownish-black when they mature. Symptoms and Signs. Abstract: Grey leaf spot is a serious yield-reducing disease of maize (Zea mays) in many parts of the world where this crop is cultivated. Symptoms: Disease is characterized by long elliptical greyish-green or tan lesions on the leaves measuring 2.5 to 25 cm in length and up to 4 cm in width. The causal organism of sugarcane leaf blight and the taxonomic status of the pathogen involved were, therefore, reinvestigated. The causal organism associated with the disease is Cercospora zeae-maydis. Single-conidial cultures were recovered from maize leaves with typical disease symptoms sampled from several fields in South Africa, Zambia and Zimbabwe. 3. These lesions become pale gray to tan as they enlarge in size from 25 mm to 150 mm or longer (Figure 2). Two potential sibling species have been recognized as Groups I and II. Two potential sibling species have been recognized as Groups I and II. race 3. Grey leaf spot is a serious yield-reducing disease of maize (Zea mays) in many parts of the world where this crop is cultivated. The extent to which gray leaf spot damages crop yields can be estimated based on the extent to which leaves are infected relative to grainfill ().Damage can be more severe when developing lesions progress past the ear leaf around pollination time. By 1943, the disease was observed causing extensive leaf blighting in Tennessee and Kentucky, reaching severities as i high as 94% (29). Gray leaf spot starts as small necrotic (dead tissue) light-tan spots. Blighted sugarcane leaves were collected from 25 locations, and 1 Published with the approval of the Director of the Taiwan Sugar Research Institute. Curvularia pallescens ), and >Pseudocochliobolus eragrostidis (syn. These expand in length to become rectangular and can reach 2 inches but they are limited within leaf veins (regular). 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